The 'Royle Family' star, who previously fought off both bladder and eye cancer, has been quietly recovering from treatment and although she faced moments of "grave" concern she is a fighter a has had a "positive outlook".

A source told The Sun newspaper: "Put it like this -- at times in the hospital there were very grave areas of concern. The chemotherapy was really intensive.

"But she's a fighter. After two weeks of recovery at home, she came on leaps and bounds. She has a positive outlook and is winning this battle."

Caroline, 50, went public with her secret illness in order to help raise £3.4 million to improve care for cancer patients in Manchester, where she received great care and support from the nurses who were "brilliant" during her treatment.

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The 'Mrs Merton' star has now backed the Macmillan Cancer Improvement Partnership, which will seek to bring together doctors, hospitals, patients and the council to improve cancer care in that area.

The source explained: "Caroline wanted to keep the illness under wraps while undergoing treatment.

"She didn't lose any weight during chemo but she did lose all her hair.

"The one group of people she really wants to thank are the Macmillan nurses, who were brilliant throughout. Over the next few months she faces further chest X-rays and blood tests. She will be in remission for five years."

(Image: PA)

The actress-and-writer and her brother, Patrick, were both born with retinal cancer, leaving her near-blind in one eye and her brother will undergo checks too.

The source confirmed: "This cancer of the lung is not caused by smoking -- it's genetic. It affects only about one per cent of the population and her brother Patrick will have to get checked out as well."